The Paleocene Epoch was important in the evolution history of the mam-mal and vice-versa

the later is important to the division of the former.ButCenozoic basins in Eastern China are always rich in microfossils while mammalscould seldom be found

that is why the study of micropaleontological assem-blages has become the key point to the stratigraphic division and correlation.Nanxiong Basin

Guangdong Province

is not only rich in mammal fossils

but also has plentiful microfossils.The Shanghu Formation

as the representa-tive of the Middle-Lower Paleocene

and known in rich Bemalambda assemblage

is associated with ostracods mainly represented by Porpocypris

Parailyocypris taizhouensis and Cypridea with radial sulcus.These ostracods

with some mem-bers of the Parailyocypris make up a transitional type of the Meso-Cenozoic Porpocy-pris-Parailyocypris-Cypridea assemblage;while in the Nongshan Formation

therepresentative of the Upper Paleocene

the extinct Bemalambda are replaced bythe development of Archaeolambda

Phenacolophus and Arclostylops associated with largely breading Sinocypris-Parailyocypris chanzhouensis-Eucypris assemblage of Cenozoic ostracods.The formal transitional to later predominant featuresof ostracods evolution is fit well for that of charophytes and sporo-pollen.Based on the correlation mentioned above

the disputed strata which contain microfossils only are studied in this paper

i.e.the Taizhou Formation of Su-bei Basin

except containing the same micrafossil assemblage as the Shanghu Formation

having more Cypridea fossils with enormous surface varieties

justthe same as charophytcs and sporo-pollen

constitutes a distinctive transitionalzone quite different from that of Cretaceous;the ostracods of the Dalangshan Formation

Sanshui Basin

characterized with the Shanghu and Taizhou For-mations

mainly belongs to transitional assemblage.So it is appropriate to con-sider both the Taizhou and Dalangshan Formations to be the Lower-Middle Paleocene.The 3rd and 4th members of the Funing Formation in Subei Basin

though contain more new species

yet Sinocypris funingensis

S.excelsa

S.multipuncta and Parailyocypris in the strata are all important members of the Nong-shan Formation

they may thus be correlated each other.